condition mean min max ZT0-3 17.6772 17.6772 17.6772 ZT4-7 12.90475 12.90475 12.90475 ZT8-11 13.686250000000001 13.686250000000001 13.686250000000001 ZT12-15 16.5819 16.5819 16.5819 ZT16-19 18.270249999999997 18.270249999999997 18.270249999999997 ZT20-23 21.3831 21.3831 21.3831